Manufacturing a physical medium configured to store data

ABSTRACT

A method and system. A layout design of invisible information to be printed with invisible ink in a book is generated. The invisible information includes a Universal Resource Locator (URL) of an address of a web server at which additional information is located. The URL is encoded in a code within the invisible information. The additional information is associated with an article.

This application is a continuation application claiming priority to Ser.No. 14/591,080, filed Jan. 7, 2015, now U.S. Pat. No. 9,230,201, issuedJan. 5, 2016, which is a continuation of Ser. No. 14/149,894, filed Jan.8, 2014, U.S. Pat. No. 9,001,389, issued Apr. 7, 2015, which is aContinuation of Ser. No. 13/572,841, filed Aug. 13, 2012, U.S. Pat. No.8,659,787, issued Feb. 25, 2014, which is a continuation of Ser. No.11/993,975, filed Dec. 27, 2007, U.S. Pat. No. 8,259,342, issued Sep. 4,2012.

TECHNICAL FIELD

The present invention generally relates to an information processingtechnique. More particularly, the present invention relates to atechnique for generating print data of invisible information to beprinted on a physical medium, and a technique for manufacturing thephysical medium on which the invisible information is printed.

BACKGROUND ART

There are ink compositions which are colorless and invisible underordinary visible light but emit light and become visible in response toillumination of light at a specific wavelength such as ultravioletlight. In general, such an ink composition is called invisible ink. As aspecific example of invisible ink, Japanese Patent Application Laid-OpenNo. 11-279474 (Patent Document 1) discloses an ink composition (see achemical formula in FIG. 18) containing a fluorescent compound ofarylsulfonic acid and tertiary amine.

An application of invisible ink is disclosed in Japanese PatentApplication Laid-Open No. 2003-296659 (Patent Document 2) as a method ofdownloading information from a server on a network using a QR code as akind of two-dimensional bar code written in invisible ink. According toan embodiment described in Japanese Patent Application Laid-Open No.2003-296659, a publisher prints a QR code in an invisible ink(transparent material) absorbing infrared rays to overlap an articleprinted in visible black ink on a magazine. Then, a reader of themagazine uses a camera-equipped cellular phone to which infrared raysare emitted to recognize the QR code so as to extract a URL from therecognized QR code. Based on the extracted URL, the reader downloadsinformation from a publisher's server.

[Patent Document 1] Japanese Patent Application Laid-Open No. 11-279474

[Patent Document 2] Japanese Patent Application Laid-Open No.2003-296659

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

Upon recognizing and extracting invisible information taken with adigital camera and printed in invisible ink, it can be difficult torecognize invisible information depending on the state of visibleinformation printed in a superimposed manner. Even if the visibleinformation does not interfere with the recognition of the invisibleinformation, the extraction accuracy of the information could bedegraded depending on the condition of a print medium (such as thequality of paper or stain on paper). Further, the state of browsing theprint medium (such as a folded state of paper or the brightness of alocation where to view the print medium) could also degrade theextraction accuracy. Thus, depending on the print state and/or thebrowsing state, there are cases where sufficient extraction accuracy ofthe invisible information cannot be obtained.

In such cases, it is necessary to optimize print data of invisibleinformation. However, on the existing technical conditions, there are noways of obtaining print data of automatically optimized invisibleinformation and using such print data to print invisible information ona physical medium on which visible information is to be printed.

The present invention has been made to solve the above problems, and itis an object to provide a system, method, and a program for generatingdata for use in printing invisible information, and a method ofmanufacturing a physical medium whereupon invisible information isprinted.

Means for Solving the Problems

In order to solve the problems, a system for generating print data ofinvisible information to be printed on a physical medium such as paper,plastic, or cloth is provided. The invisible information is printed onthe medium, on which visible information is printed, and extracted usingan apparatus having a shooting function. The system comprises: means forstoring layout data of visible information to be printed on the physicalmedium; means for storing layout data of invisible information; meansfor calculating extraction accuracy of the invisible information usingthe layout data of the visible information and the layout data of theinvisible information; means for determining whether the extractionaccuracy of the invisible information meets a predetermined condition;and means for generating data for printing the invisible informationfrom the layout data of the invisible information if the extractionaccuracy meets the predetermined condition.

Preferably, the calculating means calculates the extraction accuracy ofthe invisible information based on characteristic data of ink to be usedfor printing the visible information, characteristic data of ink to beused for printing the invisible information, characteristic data of thephysical medium, and/or predicted data of extraction environment of theapparatus provided with the shooting function. For example, if thephysical medium is paper, the characteristic data of the physical mediumcan include information on the quality of paper, stain on paper, etc.The predicted data of the extraction environment can include informationsuch as, for example, the performance of a light-emitting element formaking the invisible information visible, a light-emitting intensity, ashooting distance, a shooting angle, the brightness upon shooting, etc.

The system can also comprise means for generating corrected layout dataof the invisible information when the extraction accuracy does not meetthe predetermined condition. The calculating means and the determiningmeans can process the corrected layout data of the invisibleinformation.

Preferably, the system further comprises means for sending a feedbackrelated to the layout data to the means for generating the correctedlayout data of the invisible information when the extraction accuracydoes not meet the predetermined condition. In this case, it ispreferable to provide means for optimizing the layout data of theinvisible information based on the feedback in order to generate thecorrected layout data of the invisible information.

Preferably, the layout data includes an image pattern representing allor part of the invisible information. The image pattern can be atwo-dimensional bar code representing the invisible information.Further, the optimizing means can change the arrangement of the layoutdata, deform all or part of the image pattern, change the size of all orpart of the image pattern, increase or decrease the number of imagepatterns, and/or increase the ability to correct an error in the imagepattern.

The system can further be provided with a printer for printing theinvisible information based on data for printing the invisibleinformation.

The system can be further provided with a server including means forstoring information related to the visible information in associationwith a specific address location, means for receiving a requestincluding information representing the specific address location from anapparatus for extracting invisible information, and means for sendingthe information related to the visible information to the apparatus forextracting the invisible information in response to the request.

The system can further be provided with an apparatus including means foruploading the information related to the visible information to theserver, means for sending the visible information, and means for sendingthe specific address location associated with the visible informationuploaded to the server.

As described above, the present invention has been described as a systemfor generating print data of invisible information, the presentinvention can also be understood as a method, a program, or a programproduct. The program product can, for example, include a storage mediumon which the above-mentioned program is stored, or a medium fortransmitting the program.

The present invention can further be understood as a method ofmanufacturing a physical medium on which invisible information to beextracted by an apparatus provided with visible information and shootingfunction is printed. The method of manufacturing such a physical mediumcomprising: a step of storing layout data of the visible information; astep of generating data for printing the visible information from thelayout data of the visible information; a step of storing layout data ofthe invisible information; a step of calculating extraction accuracy ofthe invisible information using the layout data of the visibleinformation and the layout data of the invisible information; a step ofdetermining whether the extraction accuracy of the invisible informationmeets a predetermined condition; a step of generating data for printingthe invisible information from the layout data of the invisibleinformation if the extraction accuracy meets the predeterminedcondition; a step of printing the visible information on the physicalmedium based on the data for printing the visible information; and astep of printing the invisible information on the physical medium basedon the data for printing the invisible information.

It should be noted that the above-mentioned overview of the inventiondoes not cite all of necessary features of the present invention, and acombination or a subcombination of these configuration elements can alsobe considered the invention.

Advantages of the Invention

According to the present invention, print data capable of improving theextraction accuracy of invisible information to be printed on a physicalmedium together with visible information can be generated. Further,according to the present invention, the physical medium on which theinvisible information is printed using such print data can bemanufactured.

BEST MODE FOR CARRYING OUT THE INVENTION

Although the best mode for carrying out the present invention will bedescribed based on the accompanying drawings, the following embodimentdoes not limit the invention according to the scope of claims forpatent, and all of combinations of features described in the embodimentare not necessarily required as means for solving the problems accordingto the invention.

Further, the present invention can be embodied in many different modes,and interpretation of the invention should not be limited to thedescription contents of the embodiment. It should also be noted thatmeans for solving the problems according to the invention does notrequire all combinations of features described in the embodiment.Throughout the description of the embodiment, the same components aregiven the same reference numerals.

FIG. 1 is a high level conceptual diagram of the embodiment of thepresent invention. The embodiment of the present invention includes anin-house system 10 of a publisher for publishing a book, a system 20 ofa printing company for printing the book, and a cellular phone 30 of areader who purchases the book. Note that the medium on which invisibleinformation is printed is paper in the embodiment of the presentinvention, but the medium is not limited thereto. For example, thepresent invention can, of course, be applied to such a case whereinvisible information is printed on different physical media such as aplastic product like a credit card and a cloth product like clothes.

The in-house system 10 of the publisher according to the embodiment ofthe present invention includes an author's computer 11 and an editor'scomputer 12 communicable with each other through an intranet 14, and aweb server 13 for publishing publisher's information. In the embodimentof the present invention, the intranet 14 connects the computers usingTCP/IP (Transmission Control Protocol/Internet Protocol). In theintranet 14, computers to communicate with each other using IP addressesrepresented as global addresses or local addresses are identified.

The author's computer 11 has a function for enabling the author tocreate an article draft to be inserted in the book and additionalinformation related to the article. In the embodiment of the presentinvention, an ordinary word processing software such as LOTUS WORD PRO®offered by International Business Machines, Microsoft Word® offered byMicrosoft Corporation, or Ichitaro® offered by Just System, is installedin the author's computer 11.

The author can transmit the created article draft from the author'scomputer 11 to the editor's computer 12 through the intranet 14.Further, the author can upload additional information of the createdarticle from the author's computer 11 to the web server 13 so that thereader can access the additional information. In the embodiment of thepresent invention, it is preferable that the address location of theuploaded additional information (URL (Uniform Resource Locator) on theInternet in the embodiment of the present invention) be transmitted fromthe author's computer 11 to the editor's computer 12 together with thecreated article draft in order to print it in the book as invisibleinformation.

The editor's computer 12 has a function for creating print datanecessary for editing and/or layout of the article and the like receivedfrom the author's computer 11 in order to produce the book. Note herethat the editor's computer 12 has a function for generating print dataof invisible information to be printed in invisible ink in the book inaddition to the article printed in visible ink in the book. Theinvisible information can be represented by figures such as characters,but in the embodiment of the present invention, the invisibleinformation is represented by a two-dimensional bar code (so-called QRcode).

In the embodiment of the present invention, the invisible informationcontains a URL as additional information received and uploaded from theauthor's computer 11 together with the created article draft, but thepresent invention is not limited thereto. In other words, information asinvisible information other than the URL can be received from anothercomputer or the editor can create the information. The editor's computer12 can be implemented by installing DTP (Desktop Publishing) softwarehaving additional functions. In the embodiment of the present invention,the created print data is recorded on a CD-R as a common recordingmedium, and delivered to the printing company. However, it is understoodby those skilled in the art that the publisher can use any otherrecording media, or send the print data to the printing company througha network.

The web server 13 has a function for storing data, uploaded from acomputer connected to the intranet 14 such as the author's computer 11or the editor's computer 12, in a predetermined format in associationwith a specific address location. The web server 13 also has a functionfor providing the stored data to the reader or the like in response to arequest from the reader or the like via the Internet 40.

The system 20 of the printing company in the embodiment of the presentinvention includes a computer 21 and a printer 22 connected to eachother in the printing company. The computer 21 of the printing companyhas functions for reading data from the recording medium storing theprint data (the CD-R with the print data stored thereon in theembodiment of the present invention) and storing it in a built-inrecording unit. The computer 21 of the printing company also has afunction for having the printer 22 print a book 23 based on the printdata stored in the built-in recording unit.

The printer 22 has a function for producing the book 23 using variousvisible inks such as black ink and/or color inks. Although the printer22 can, of course, be a consumer-type small printer, it is preferablethat the printer 22 be a large offset printer or the like because theembodiment of the present invention assumes mass production of the books23. It is to be noted that the printer 22 also has a function forprinting invisible information 24 using invisible ink. It should benoted that those skilled in the art can appropriately design thefunction for printing the invisible information in such a manner to addthe function to any conventional printer 22.

FIGS. 8 and 9 show image examples of a page of the book 23 produced onthe printer 22 according to the embodiment of the present invention.FIG. 8 shows an image of the page as viewed under normal visible light.In this case, the reader can view only the normal article, i.e., thereader can browse the article normally.

In the embodiment of the present invention, if the reader illuminatesthe page with light of a special wavelength, the invisible information24 appears as shown in FIG. 9. In the embodiment of the presentinvention, the invisible information 24 is a QR code as a kind oftwo-dimensional bar code illustrated in FIG. 10. A specification of theQR code is standardized as ISO (ISO/IEC 18004) or JIS (JIS-X-0510).Since the information can easily be obtained, its detailed descriptionwill be omitted here. In the embodiment of the present invention, thereader of the book 23 reads the QR code using a camera-equipped cellularphone 30 provided with a light-emitting element 607 emitting light ofthe special wavelength and decodes the QR code using a processingfunction of the cellular phone to enable the reader to acquire theinvisible information.

The cellular phone 30 of the reader in the embodiment of the presentinvention has a function as the digital camera function and a functionfor accessing the Internet 40 via a base station 41. Further, thecellular phone 30 has a function for allowing the reader who subscribesto the book 23 to use the digital camera function of the cellular phone30 to decode the two-dimensional bar code 24 as the read invisibleinformation. The reader can access the additional information stored inthe web server 13 using the function for accessing the Internet 40 viathe base station 41 based on the URL for the additional informationassociated with the article of the book contained in the invisibleinformation.

In the embodiment of the present invention, a PDC (Personal DigitalCellular) system can, for example, be employed as a wirelesscommunication system between the cellular phone 30 of the reader and thebase station 41, but the present invention is not limited thereto. Forexample, any other system such as a CDMA (Code Division Multiple Access)system can be employed appropriately.

In the embodiment of the present invention, the computers can beconnected over the Internet 40 using TCP/IP like through the intranet14. Like in the intranet 14, computers to communicate with each otherare identified in the Internet 40 using IP addresses represented byglobal addresses or local addresses.

FIG. 2 is an outline view showing an example of an informationprocessing apparatus 200 suitable for implementation of the author'scomputer 11, the editor's computer 12, the web server 13, or thecomputer 21 of the printing company according to the embodiment of thepresent invention. The information processing apparatus 200 includes amain body 201, a keyboard 306, a mouse 307, and a display device 311. Ause of the information processing apparatus 200 can operate the keyboard306 and the mouse 307 to do desired work such as creation and editing ofa document or printer control. The user can also view the visuallydisplayed information on the display device 311 to check the workingcondition on an as-needed basis.

FIG. 3 is a diagram showing an exemplary hardware configuration of theinformation processing apparatus 200 suitable for implementation of theauthor's computer 11, the editor's computer 12, the web server 13, orthe computer 21 of the printing company according to the embodiment ofthe present invention. The information processing apparatus 200 includesa CPU (Central Processing Unit) 301 and a main memory 303 connected to abus 302. Further, removable storages (external storage systems capableof replacing recording media) such as hard disk drives 313 and 330,CD-ROM drives 326 and 329, a flexible disk drive 320, an MO drive 328,and a DVD-ROM drive 331 are connected to the bus 302 via an IDEcontroller 325 and a SCSI controller 327.

Then, a flexible disk, such as an MO, a CD-ROM, or a DVD-ROM is insertedinto a corresponding removable storage. Computer program codes can berecorded on these storage media, the hard disk drives 313 and 330, and aROM 314 to cooperate with the an operating system to give instructionsto the CPU and the like so as to execute the present invention. Thecomputer program is executed by loading it to the main memory 304. Thecomputer program can also be compressed or divided and stored in aplurality of media.

The information processing apparatus receives input from user interfacedevices such as the keyboard 306 and mouse 307 via a keyboard/mousecontroller 305. The information processing apparatus 200 is connected tothe display device 311 via a DAC/LCDC 310 to provide visual data to theuser.

The information processing apparatus is connected to a network through anetwork adapter 318 (such as an Ethernet® card or a token ring card) sothat it can communicate with other computers and the like. Though notshown, the information processing apparatus 200 can be connected to aprinter through a parallel port or to a modem through a serial port.

As described above, it will be easily understood that the informationprocessing apparatus 200 suitable for implementation of the author'scomputer 11, the editor's computer 12, the web server 13, or thecomputer 21 of the printing company according to the embodiment of thepresent invention can be an information processing apparatus such as amainframe computer, a workstation, or a normal personal computer, or acombination of these computers. Note that these configuration elementsare just illustrative examples and the invention does not enumerate allof necessary features of the present invention.

Of course, it can be easily understood by those skilled in the art thatvarious changes are possible, such as to implement each of the hardwareconfiguration elements of the information processing apparatus 200 usedin the embodiment of the present invention by means of a plurality ofmachines to distribute and execute each function. These changes shouldbe included within the scope of the present invention.

The information processing apparatus 200 can employ an operating systemsupporting a GUI (Graphical User Interface) multi-window environment,such as a Windows® operating system offered by Microsoft Corporation, anAIX® offered by International Business Machines Corporation, a Mac OS®offered by Apple Computer Incorporated, or Linux®.

The information processing apparatus can also employ an operating systemsupporting a character-based environment, such as PC-DOS offered byInternational Business Machines Corporation or MS-DOS offered byMicrosoft Corporation. Further, the information processing apparatus 200can also employ a real-time OS as the operating system such as OS Openoffered by International Business Machines Corporation and an operatingsystem to be built in a network computer such as Java® OS.

As mentioned above, it can be understood that the information processingapparatus 200 used in the embodiment of the present invention is notlimited to a specific operating system environment.

FIG. 4 is a functional block diagram of the editor's computer 12according to the embodiment of the present invention. Note that eachelement shown in the functional block diagram of FIG. 4 and the like canbe so implemented that the hardware resources cooperate with software byloading the computer program stored in the hard disk drive 313 to themain memory 304 and causing the CPU 301 to read the computer program inthe information processing apparatus 200 having the hardwareconfiguration illustrated in FIG. 3.

The editor's computer 12 includes a visible information storage section401, an invisible information storage section 402, a printingcharacteristic data storage section 403, an extraction environment datastorage section 404, a visible information layout generating section405, an invisible information layout generating section 406, anextraction accuracy calculating section 407, an extraction resultdetermining section 408, a feedback section 409, and a print datagenerating section 410. The editor's computer 12 also includes an inputsection 411, a display section 412, and a network interface 413 as itsinterface with a user or an external computer.

The visible information storage section 401 stores, in a digital format,information to be printed in visible ink on the physical medium for thebook including the article draft crated on the author's computer 11. Theinvisible information storage section 402 stores, in a digital format,invisible information received from other computers including theauthor's computer 11 through the network interface 413 or invisibleinformation created by the editor. In the embodiment of the presentinvention, the invisible information includes an URL for the additionalinformation of the article created on the author's computer 11. Theprinting characteristic data storage section 403 stores, in a digitalformat, printing characteristics for the book, such as the color ofpaper or stain on the paper, and information related to ink colors usedin printing the visible information and/or invisible information. Theextraction environment data storage section 404 stores, in a digitalformat, an environment in which the reader extracts the invisibleinformation, such as an expected shooting performance of the digitalcamera, the performance of the light-emitting element emitting light ofa special wavelength (e.g., LED characteristics), a shooting distance, ashooting angle, and information related to the brightness upon shooting.

The visible information layout generating section 405 generates layoutdata of the visible information based on the data stored in the visibleinformation storage section 401. In the embodiment of the presentinvention, since the layout data of the visible information is generatedmanually or semi-automatically in response to input from the editor viathe input section 411, the detailed description of the operations willbe omitted because it is not essential of the present invention. Theinvisible information layout data generating section 406 generates thelayout data of the invisible information based on the data stored in theinvisible information storage section 402. In the embodiment of thepresent invention, it is assumed that the layout data of the invisibleinformation is automatically generated, but the reader can adjust thelayout data of the invisible information by operating the input section411. Note that in the embodiment of the present invention, the layoutdata of the invisible information includes image data of a QR code as akind of two-dimensional bar code as an image pattern representing all orpart of the invisible information.

The extraction accuracy calculating section 407 simulates the extractionof the invisible information to calculate the extraction accuracy of theinvisible information using the layout data of the visible informationgenerated by the visible information layout generating section 405 andthe layout data of the invisible information generated by the invisibleinformation layout generating section 406. In the embodiment of thepresent invention, data stored in the printing characteristic datastorage section 403 and the extraction environment data storage section404 are used for simulation. The extraction result determining section408 determines whether the extraction accuracy of the invisibleinformation calculated by the extraction accuracy calculating section407 meets a predetermined condition. If the extraction resultdetermining section 408 determines that the extraction accuracy does notmeet the predetermined condition, the invisible information layoutgenerating section 406 generates new layout data of the invisibleinformation to activate the extraction accuracy calculating section 407and the extraction result determining section 408 for the new layoutdata of the invisible information.

When the extraction result determining section 408 determines that theextraction accuracy does not meet the predetermined conditions, thefeedback section 409 sends the invisible information layout generatingsection 406 feedback information to be referred to upon generating thenew layout data of the invisible information. In the embodiment of thepresent invention, the invisible information layout generating section406 optimizes the layout data of the invisible information based on thefeedback to create the new layout data of the invisible information. Theoptimization of the layout data includes, for example, a change in thearrangement of elements contained in the layout data, a deformation ofall or part of the QR code, a change in size, an increase or decrease innumber, and a change in error correcting capability, but the presentinvention is not thereto.

When the extraction result determining section 408 determines that theextraction accuracy meets the predetermined condition, the print datagenerating section 410 generates print data of the invisible informationfrom the layout data of the invisible information. The print datagenerating section 410 can also generate print data of the visibleinformation from the layout data of the visible information from thevisible information layout generating section 405. In the embodiment ofthe present invention, the visible information and/or print data ofinvisible information is stored on a CD-R as a recording medium releasedto the public and easily available, and delivered to the printingcompany 20.

The input section 411 receives input from the editor to allow the editorto adjust the layout of visible information and/or invisibleinformation. The display section 412 displays the layout of visibleinformation or invisible information currently processed or thecalculation or determination result of the extraction accuracy. Theeditor can operate the input section 411 while referring to informationdisplayed in the display section. The network interface 413 has afunction for exchanging information with the intranet 14. The editor'scomputer 12 receives information such as the article draft from theauthor's computer 11 via the network interface 413 to store it in thevisible information storage section 401 or the like.

FIG. 5 is a functional block diagram of the web server 13 according tothe embodiment of the present invention. The web server 13 includes acommunication interface 503, an additional information storage section504, and a web page generating section 505. Those skilled in the artwill appreciate that the web server 13 can easily be built byintroducing software for building a web server, such as free softwareApache or IIS product offered by Microsoft Corporation, into theinformation processing apparatus having a hardware configurationillustrated in FIG. 3.

The communication interface 503 stores data of additional informationuploaded through a routing line 501 from a computer connected to theintranet 14, such as the author's computer 11 or the editor's computer12, in the additional information storage section 504 in associationwith the URL for the additional information. The communication interface503 can also transfer, to the web page generating section 505, a requestincluding a URL for additional information received through a routingline 502 from the cellular phone 30 of the reader. In response to therequest received from the cellular phone 30 of the reader via thecommunication interface 503, the web page generating section 505 cancreate a web page based on the additional information stored in theadditional information storage section 504 and send it back to thecellular phone 30 through the routing line 502.

FIG. 6 is an outline view of the cellular phone 30 of the readeraccording to the embodiment of the present invention. It is understoodfrom FIG. 6 that the cellular phone 30 includes an antenna 601, adisplay 603, an input section 604, a camera 606, a light-emittingelement 607, a speaker 608, and a microphone 609. From its appearance,there is no difference from conventional cellular phones except that thecellular phone 30 of the reader is provided with the light-emittingelement 607 emitting light of a specific wavelength to make theinvisible ink visible. The light-emitting element 607 can be acommercially available LED (Light Emitting Diode).

FIG. 7 is a functional block diagram of the cellular phone 30 of thereader according to the embodiment of the present invention. It isunderstood from FIG. 7 that the cellular phone 30 includes a radiosection 602, a memory 605, and a controller 610 in addition to theantenna 601, the display 603, the input section 604, the camera 606, thelight-emitting element 607, the speaker 608, and the microphone 609described in connection with FIG. 6.

The antenna 601 has a function for receiving a radio wave from the basestation 41 and sending a radio wave from the radio section 602 to thebase station 41. The radio section 602 modulates the radio wave receivedat the antenna into an electric signal and demodulates an electricsignal into a radio wave. The display 603 shows the information to anoperator so that the operator will operate the cellular phone using theinput section 604 while referring to the displayed information. Thememory 605 is used to store information such as an image shot with thecamera 606. The camera 606 includes a lens capable of taking a picture.The light-emitting element 607 can emit light of a special wavelength toilluminate the invisible information. The operator can not only hear avoice sound through the speaker 608, but also input his or her voicethrough the microphone 609. These configuration elements are controlledby the controller 610.

FIG. 11 is a flowchart 1100 showing an outline of a flow of print datacreation for a book according to the embodiment of the presentinvention. The processing starts at step 1101, and in step 1102, theauthor uses the word processing software installed on the author'scomputer 11 to create an article draft and additional informationassociated with the article.

The processing proceeds to step 1103 in which the author's computer 11sends the article draft to the editor's computer 12. Further, in step1103, the author's computer 11 uploads additional information to the webserver 13.

Next, in step 1104, the article to be printed in visible ink is editedand its layout is designed. In the embodiment of the present invention,it is considered at a stage of designing the layout of invisibleinformation how the layout of the article to be printed in visible inkis designed. Therefore, in the embodiment of the present invention, itis preferable that this step be executed before designing the layout ofthe invisible information.

Then, the processing proceeds to step 1105 in which the layout of theinvisible information is designed. In the embodiment of the presentinvention, the invisible information is represented by a QR code as akind of two-dimensional bar code. This processing step will be describedin detail later. Next, in step 1106, print data is generated based onthe layout of the article and the invisible information defined in steps1104 and 1105. The generated print data is stored on a recording mediumsuch as a CD-R, and delivered to the printing company. Then, theprocessing proceeds to step 1107 to end the print data creationprocessing for the book.

Next, processing performed in the in-house system 20 of the printingcompany which has received the print data in the embodiment of thepresent invention will be described with reference to a flowchart 1200of FIG. 12. The processing starts at step 1201, and in step 1202, theprinting company takes delivery of the print data stored on therecording medium, and captures it into the computer 21 of the printingcompany. Then, the processing proceeds to step 1203, in which thecomputer 21 is operated to control the printer at the printing companyto print the article information in visible ink and the QR code ininvisible ink. After that, the printing company binds a book and thelike to produce the book. Next, in step 1204, the produced book isshipped and delivered to the reader through the market.

Further, processing for enabling the reader who received the book to getadditional information of an article in the book in the embodiment ofthe present invention will be described with reference to a flowchart ofFIG. 13. The processing starts at step 1301, and in step 1302, thereader reads the purchased book. Then, the processing proceeds to step1303. Suppose in step 1303 that the reader finds an article in the bookto which additional information is attached and wants to get theadditional information. In such a case, the reader emits thelight-emitting element 607 on the cellular phone 30 to illuminate theinvisible information and takes a picture of the illuminated informationwith the camera 606 in the next step 1304 to capture an image of the QRcode into the cellular phone 30. Then, in step 1305, the QR code isdecoded to acquire the URL for the additional information. Then, theprocessing proceeds to step 1306 to access the web server 13 using thedecoded and acquired URL for the additional information in order todownload the additional information in step 1307. The reader can checkthe downloaded additional information, for example, on the display 603of the cellular phone 30. After that, the processing proceeds to step1308 to end the processing.

Next, processing for generating layout data of invisible information asdescribed at step 1105 of FIG. 11 will be described in detail withreference to FIGS. 14 to 16. In the embodiment of the present invention,the printer 22 prints the invisible information on a page of the book asa square QR code as an example. Note here that the shape of the QR codedoes not need to be a square and the code does not need to be the QRcode to implement the present invention.

The processing starts at step 1401, and in step 1402, the minimum andmaximum values indicative of the size of the QR code representing theinvisible information (hereinafter referred to as “code size”) aredecided using data stored in the printing characteristic data storagesection 403 and the extraction environment data storage section 404.Specifically, the minimum value of the code size is calculated from thenumber of pixels in the camera, for example. On the other hand, themaximum value of the code size is decided, for example, based on theangle and intensity of the light-emitting element (LED), shootingdistance, and brightness upon shooting. It should be noted that thoseskilled in the art can appropriately design methods for calculatingthese maximum and minimum values. In the embodiment of the presentinvention, the code size means a side length (Q in FIG. 17) of the QRcode including an auxiliary portion.

Next, in step 1403, an image of the physical medium for printing the QRcode is digitized to find a blank space larger than the minimum value ofthe code size decided in step 1402. In the embodiment of the presentinvention, the blank space means a square area in which the standarddeviation of brightness value of the image is smaller than a certainvalue T1. If a blank space whose one side is larger than the minimumvalue of the code size decided in step 1402 is found, the processingproceeds to step 1405 to decide to print the QR code in the found area.In other words, in step 1404, if one or more square blank spaces whoseone side E meets E=>D where D is the minimum code size (on conditionthat the blank space can be rotated), the processing proceeds from Yesof step 1404 to step 1405.

In the embodiment of the present invention, suppose that there are aplurality of printable blank spaces. If there are blank spaces that meetAn=0 where An is the rotating angle of the QR code, a blank space whoseone side E is the largest is selected as the printing location of the QRcode. On the other hand, if there is no blank space that meets An=0, ablank space whose one side E is largest from among those having rotatingangle An≠0 is selected as the printing location of the QR code. Ineither case, the offset (x, y) and the rotating angle An are output asparameters. After the processing step 1405 is executed, the processingproceeds to step 1408 to end the processing.

On the other hand, if no square blank space whose one side E meets E=>Dis found in step 1404, the processing proceeds from No of step 1404 tostep 1406. In step 1406, a digital image entirely printed in invisibleink on an image of a physical medium to be printed based on thecondition used in step 1402.

After the digital image entirely printed in invisible ink is created,the processing proceeds to step 1407. In step 1407, an image is createdby performing post-processing on the print image of the QR code(referred as to “I0: No Ink”) and an image is created by performingpost-processing on the image of the physical medium to be printed(referred as to “I1: With Ink”). In the embodiment of the presentinvention, the term “post-processing” means that the image is processedto reflect events likely to affect various images upon taking a pictureof the QR code and extracting invisible information (for example,sampling depending on the number of pixels of the camera, image blurdepending on paper properties, etc.). In the embodiment of the presentinvention, the image “I1: With Ink” has, on its top layer, a color theamount of which is largest as a component of the invisible ink (e.g., R,G, B, Y, Cb, or Cr) and the image “I0: No Ink” does not have the coloron its top layer. Further, in step 1407, an average brightness value ofa square having search step S as its one side length is calculated andheld for each of the images “I0: No Ink” and “I1: With Ink.” Theprocessing proceeds to a flowchart of FIG. 15 via step 1408.

The flowchart 1500 of FIG. 15 starts at step 1501. In a step thatfollows step 1501, each of the images “I0: No Ink” and “I1: With Ink” isused to calculate the extraction accuracy of the invisible QR code whilechanging the size of the QR code and the rotating angle An. Instead ofchanging the size of the QR code and the rotating angle An, theextraction accuracy can also be calculated while changing the aspectratio or the like of the QR code. However, for simplicity ofillustration, the embodiment of the present invention assumes that theaspect ratio of the QR code is fixed.

The processing starts at step 1501, and in step 1502, the initial valueof the rotating angle An is set to 0 deg. Next, in step 1503, theinitial value of the QR code size Q is set to the maximum value of thecode size, and the processing proceeds to step 1504. In step 1504, thelocation of the QR code where the invisible information meets thepredetermined extraction accuracy condition is searched while shiftingthe QR code every search step S (every C=kS as a cell unit (black orwhite square) of QR code, where C is the size of one side and k is aninteger equal to or greater than 1). The following describes the detailsof an example of a search algorithm in step 1504 with reference to aflowchart of FIG. 16.

FIG. 16 is a flowchart 1600 showing an example of the search algorithmin step 1504 of the flowchart of FIG. 15. The processing starts at step1601, and in step 1602, the offset value (x, y) (upper-left endposition) of the QR code to be shifted is initialized as (0, 0).Further, in step 1602, the initial value of Error_min representing theminimum error value is initialized as T (where T is the number of errorcorrectable cells+1 in the QR code).

Next, in step 1603, an image of the QR code to be printed is generatedusing each of the images “I0: No Ink” and “I1: With Ink.” Specifically,image portions to be printed (black portions of the QR code) are scannedin units of S×S from the image “I1: With Ink,” image portions not to beprinted (white portions of the QR code, i.e., outside the range of QRcode) are scanned in units of S×S from the image “I0: No Ink,” and bothscanned images are combined to generate the image of the QR code.Further, in step 1603, position detection patterns 1701 contained in theQR code are searched using the image of the generated QR code. Theposition detection patterns 1701 are searched according to the followingcriteria: (1) they do not overlap each other, and (2) it is determinedwhether three position detection patterns can be detected on conditionthat the distance between the position detection patterns (for example,in case of two position detection patterns shown in FIG. 17, thedistance between the right end of the left-hand position detectionpattern and the left end of the right-hand position detection pattern)is twice or more the length of one side of the minimum positiondetection pattern (hereinafter referred as to “position detectionpattern condition”).

The following is an example of a method of determining whether threeposition detection patterns can be detected. First, it is assumed thatthe average brightness value of a position search code area to bedetected is L, and the average brightness value of each S×S square to besearched and having the offset (x,y) is M(x,y). Then, f(x,y) is definedas follows:f(x,y)=1 (if M(x,y)<L)f(x,y)=0 (otherwise)  (Equation 1)

Next, if the length of consecutive f(x,y)=1 or f(x,y)=0 is N1, N2, N3, .. . , and the length takes on values that fall within allowable limitsof error to which Δ₁ and Δ₂ are given. Then, if lengths that meet thefollowing condition are found in horizontal and vertical directions,respectively, and three position detection patterns can be reproducedbased on these lengths, it can be determined that three positiondetection patterns can be detected.N1:N2:N3:N4:N5=1+Δ₁:1+Δ₁:3+Δ₂:1+Δ₁:1+Δ₁  (Equation 2)

If four or more patterns that meet the “position detection patterncondition” are found, any three patterns that meet the “positiondetection pattern condition” can be selected to repeat the followingprocessing steps until the print position of the QR code is found. Inthis case, the following processing steps are repeated _(h)C₃ times at amaximum (where h is the number of patterns that meet the “positiondetection patterns condition”). Alternatively, if four or more patternsthat meet the “position detection pattern condition” are found, patternmatching can be used to select three patterns that meet “positiondetection pattern condition and are close in shape to one another sothat the selected three patterns will be processed in the followingprocessing steps.

If three position detection patterns are detected, N1, N2, N3, N4, N5values can be calculated (Equation 2) while shifting the horizontalcomponent and the vertical component of each pattern little by little todetermine the rotating angle An.

If three position detection patterns are found in step 1604, theprocessing proceeds from Yes of step 1604 to step 1605. In step 1605,the QR code area is defined based on the position detection patternsfound in step 1604 and a bit conversion is performed. For example, whenthe rotating angle An is 0, the QR code area is defined as a squarehaving the found position detection patterns as three corners. Further,if the average brightness value of an r×r square having the center pointof each C×C cell at a position (s,t) as its center of gravity (wherer<=C) is U(s,t,r) and the average brightness value of the QR code areais V, the bit conversion is performed based on a value g(s,t) defined inthe following equation 3. Specifically, cells having a value g(s,t)=1 isdefined as white and cells having a value g(s,t)=0 is defined as blackto generate the QR code in order to achieve the bit conversion in step1605.g(s,t)=1(if U(s,t,r)<V)g(s,t)=0(otherwise)  (Equation 3)

In the above description, V is the average brightness value of theoverall QR code. However, since light and shade of a color in the QRcode can vary, V can also be defined as a brightness average valueV(s,t,Z) of a square having one side length Z and (s,t) as its center.

Next, in step 1606, errors in bit conversion are counted. Specifically,the QR code to be actually printed is compared with the QR codegenerated through the bit conversion to count the number of portions inwhich black pixels are turned white and vice versa (excluding theposition detection, timing, and alignment patterns) as the number oferrors. Next, in step 1607, it is determined whether the number oferrors in bit conversion counted in step 1606 is 0. If it is determinedin step 1607 that the number of errors is 0, the processing proceedsfrom Yes of step 1607 to step 1608, and the offset value obtained at thetime is decided as the print location of the QR code.

If it is determined in step 1607 that the number of errors is not 0, theprocessing proceeds from No of step 1607 to step 1609 in which thenumber of errors obtained this time is compared as to whether it issmaller than the minimum value (Error_min) of the number of previouserrors. If it is determined in step 1609 that the number of errorsobtained this time is smaller than the minimum value of the number ofprevious errors, the processing proceeds from Yes of step 1609 to step1610 in which the Error_min value is updated to the number of errorsobtained this time and offset (xb,yb) is stored. After that, theprocessing proceeds to step 1611. If it is not determined in step 1609that the number of errors obtained this time is smaller than the minimumvalue of the number of previous errors, the processing proceeds from Noof step 1609 to step 1611 without updating the Error_min value to thenumber of errors obtained this time.

On the other hand, if three position detection patterns are not found instep 1604, the processing also proceeds from No of step 1604 to step1611.

In the following steps, the above-mentioned sequence of operations arerepeated while shifting the print position of the QR code by S each timein the x direction and the y direction, respectively, with a searchrange up to X in the x direction and Y in the y direction (steps 1611through 1614). After performing these operations on the images, it isdetermined in step 1615 whether Error_min<T. If it is determined in step1615 that Error_min<T, an offset to which the minimum error value isgiven is decided to be the print position of the QR code (step 1617). Ifit is not determined that Error_min<T, the processing is ended (step1616).

In the above-mentioned processing, the image area L and the averagebrightness value V of the image need to be determined each time theprint position is shifted by S in the x direction (or y direction).However, the image area L and the average brightness value V of theimage before the print position is shifted by S can be so held that onlydifferences from those before being shifted are added to the image areaL and the average brightness value V of the image in order to speed upthe processing.

The above has described an example of the search algorithm in step 1504of the flowchart of FIG. 15 with reference to the flowchart of FIG. 16.Returning to FIG. 15, it is determined in step 1505 whether searchingfor the location of the QR code that meets the predetermined extractionaccuracy of the invisible information in the search step 1504 issuccessful. If it is determined in step 1505 that the searching issuccessful, the processing proceeds from Yes of step 1505 to step 1506in which the searched location is decided to be the print position ofthe QR code.

If it is determined in step 1505 that the searching cannot be done,these operations are performed while changing the size of the QR codeand the rotating angle An until the print location can be searched(steps 1507 through 1510). When the print location cannot be ultimatelysearched even if the operations are repeated while changing the size ofthe QR code and the rotating angle An, it is determined that printing isimpossible and the processing is ended (step 1511).

In the embodiment of the present invention, the scales of the size ofthe QR code and the rotating angle An to be changed in steps (QStep andAnStep) are specified by the editor. For example, if it is desired toperform high-speed processing, the editor can specify larger valuesrelative to each other in QStep and AnStep. On the other hand, if it isdesired to make it certain that the processing is correctly performed nomatter how long it takes, the editor can specify smaller values relativeto each other in QStep and AnStep. Note that if AnStep>=360, it meansthat the rotating angle An is not changed.

In the embodiment of the present invention, when Q takes a certainvalue, if at least one portion in which there is an error correctableoffset (x,y) is found, the processing is ended. However, anotheralgorithm as a modification for searching the minimum number of cellswith respect to all sizes and all rotating angles An can also beemployed.

As described above, according to the present invention, it is easilyunderstood that print data capable of improving the extraction accuracyof the invisible information to be printed on the physical mediumtogether with the visible information can be generated.

The above description has used the embodiment of the present invention,the present invention is not limited to the technical scope described inthe embodiment. For example, the author's computer 11, the editor'scomputer 12, and the web server 13 are illustrated as singlerespectively in FIG. 1, but they can, of course, be plural respectively.

Further, the present invention can be embodied as hardware, software, ora combination of both. As a typical example of the combination ofhardware and software, there can be cited a computer system having apredetermined program. In such a case, the predetermined program isloaded into the computer system and so executed that the programcontrols the computer system to cause the computer system to execute theprocessing according to the present invention. This program isconfigured from a set of instructions which can be expressed by anarbitrary language, code, or notation. Such an instruction set enablesthe system to perform a specific function directly or after (1)conversion to a different language, code, or notation, and/or (2)replication onto a different medium. Of course, the present inventionencompasses not only such a program itself but also a medium on whichthe program is recorded. The program for performing the function of thepresent invention can be stored in any computer readable recordingmedium, such as a flexible disk, an MO, a CD-ROM, a DVD, a hard diskdrive, a ROM, an MRAM, and a RAM. In order to store such a program ontothe computer readable medium, the program can be downloaded from adifferent computer system connected via a communication line or can bereplicated from a different recording medium. The program can also becompressed or divided into a plurality of components to store on asingle recording medium or a plurality of recording media.

It is obvious to those skilled in the art that the above-mentionedembodiment can be changed or modified in various ways. It should beunderstood that forms to which such changes and modifications are madecan be included without departing from the technical scope of thepresent invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 It is a high level conceptual diagram of a preferred embodimentof the present invention.

FIG. 2 It is an outline view showing an example of an informationprocessing apparatus suitable for implementation of an author'scomputer, an editor's computer, a web server, or a computer of aprinting company according to the embodiment of the present invention.

FIG. 3 It is a diagram showing an exemplary hardware configuration ofthe information processing apparatus suitable for implementation of theauthor's computer, the editor's computer, the web server, or thecomputer of the printing company according to the embodiment of thepresent invention.

FIG. 4 It is a functional block diagram of the editor's computeraccording to the embodiment of the present invention.

FIG. 5 It is a functional block diagram of the web server according tothe embodiment of the present invention.

FIG. 6 It is an outline view of a cellular phone of a reader accordingto the embodiment of the present invention.

FIG. 7 It is a functional block diagram of the cellular phone of thereader according to the embodiment of the present invention.

FIG. 8 It shows an image example of a page of a book produced on aprinter according to the embodiment of the present invention.

FIG. 9 It shows another image example of the page of the book producedon the printer according to the embodiment of the present invention.

FIG. 10 It shows an image example of a QR code printed on a page of thebook produced on the printer according to the embodiment of the presentinvention.

FIG. 11 It is a flowchart showing an outline of a flow of print datacreation for a book according to the embodiment of the presentinvention.

FIG. 12 It is a flowchart showing processing in an in-house system ofthe printing company which has received the print data according to theembodiment of the present invention.

FIG. 13 It is a flowchart showing processing performed by the reader whohas received the book in process of getting additional information of anarticle in the book according to the embodiment of the presentinvention.

FIG. 14 It is a flowchart showing processing for print data creation ofthe QR code to be printed as invisible information according to theembodiment of the present invention.

FIG. 15 It is a flowchart showing the processing for print data creationof the QR code to be printed as invisible information according to theembodiment of the present invention.

FIG. 16 It is a flowchart showing an example of an algorithm forsearching the location of the QR code that the invisible informationmeets a predetermined extraction accuracy condition according to theembodiment of the present invention.

FIG. 17 It is an illustration showing an image of the QR code accordingto the embodiment of the present invention.

FIG. 18 It is an exemplary chemical formula of invisible ink inBackground Art.

The invention claimed is:
 1. A method, said method comprising:generating, by a processor of a computer system, a layout design ofinvisible information to be printed with invisible ink in a book, saidinvisible information comprising a Universal Resource Locator (URL) ofan address of a web server at which additional information is located,said URL being encoded in a code within the invisible information, saidadditional information being associated with an article.
 2. The methodof claim 1, wherein the method further comprises: after said generatingthe layout design of invisible information, said processor determiningthat an extraction accuracy for extracting the invisible informationfrom an image of the code satisfies a predetermined condition; and isresponse to said determining that the extraction accuracy satisfies thepredetermined condition said processor generating print data of theinvisible information based on the generated layout design of invisibleinformation.
 3. The method of claim 1, wherein the code is a squarecharacterized by a code size equal to the length of each side of thesquare, wherein said generating the layout design of invisibleinformation comprises: determining a square space in the physical mediumin which to print the code, determining an offset that specifies theupper left corner of the square space in the physical medium; anddetermining an angle of rotation of the square space in the physicalmedium relative to a specified direction in the physical medium.
 4. Themethod of claim 3, wherein said determining the square space comprises:determining a minimum value of the code size; and finding a blank spacehave a square shape characterized by a length of each side of the squareshape exceeding the minimum value of the code size, wherein the squarespace consists of the blank space.
 5. The method of claim 3, wherein thedetermined angle of rotation is zero degrees.
 6. The method of claim 3,wherein the determined angle of rotation exceeds zero degrees.
 7. Themethod of claim 1, wherein the method further comprises: said processorgenerating a layout design of visible information to be printed withvisible ink in the book, said visible information comprising thearticle.
 8. The method of claim 1, wherein the code within the invisibleinformation is a two-dimensional bar code.
 9. A computer programproduct, comprising a computer readable hardware storage device havingcomputer readable program code stored therein, said program codecontaining instructions executable by a processor of a computer systemto implement a method, said method comprising: generating, by theprocessor, a layout design of invisible information to be printed withinvisible ink in a book, said invisible information comprising aUniversal Resource Locator (URL) of an address of a web server at whichadditional information is located, said URL being encoded in a codewithin the invisible information, said additional information beingassociated with an article.
 10. The computer program product of claim 9,wherein the method further comprises: after said generating the layoutdesign of invisible information, said processor determining that anextraction accuracy for extracting the invisible information from animage of the code satisfies a predetermined condition; and is responseto said determining that the extraction accuracy satisfies thepredetermined condition said processor generating print data of theinvisible information based on the generated layout design of invisibleinformation.
 11. The computer program product of claim 9, wherein thecode is a square characterized by a code size equal to the length ofeach side of the square, wherein said generating the layout design ofinvisible information comprises: determining a square space in thephysical medium in which to print the code, determining an offset thatspecifies the upper left corner of the square space in the physicalmedium; and determining an angle of rotation of the square space in thephysical medium relative to a specified direction in the physicalmedium.
 12. The computer program product of claim 11, wherein saiddetermining the square space comprises: determining a minimum value ofthe code size; and finding a blank space have a square shapecharacterized by a length of each side of the square shape exceeding theminimum value of the code size, wherein the square space consists of theblank space.
 13. The computer program product of claim 11, wherein thedetermined angle of rotation is zero degrees.
 14. The computer programproduct of claim 11, wherein the determined angle of rotation exceedszero degrees.
 15. The computer program product of claim 9, wherein themethod further comprises: said processor generating a layout design ofvisible information to be printed with visible ink in the book, saidvisible information comprising the article.
 16. A computer system,comprising a processor, a memory coupled to the processor, and acomputer readable hardware storage device coupled to the processor, saidstorage device containing program code executable by the processor viathe memory to implement a method, said method comprising: generating, bythe processor, a layout design of invisible information to be printedwith invisible ink in a book, said invisible information comprising aUniversal Resource Locator (URL) of an address of a web server at whichadditional information is located, said URL being encoded in a codewithin the invisible information, said additional information beingassociated with an article.
 17. The computer system of claim 16, whereinthe method further comprises: said processor generating a layout designof visible information to be printed with visible ink in the book, saidvisible information comprising the article.
 18. The computer system ofclaim 17, wherein the method further comprises: said processorgenerating print data of the visible information based on the generatedlayout design of visible information; said processor generating printdata of the invisible information based on the generated layout designof invisible information; and said processor storing, on the physicalmedium, the generated print data of the visible information and thegenerated print data of the invisible information.
 19. The computersystem of claim 18, wherein the method further comprises: after saidgenerating the layout design of invisible information, said processordetermining that an extraction accuracy for extracting the invisibleinformation from an image of the code satisfies a predeterminedcondition, wherein said generating print data of the invisibleinformation is responsive to said determining that the extractionaccuracy satisfies the predetermined condition.
 20. The computer systemof claim 19, wherein said determining that the extraction accuracysatisfies the predetermined condition comprises: simulating saidextraction of the invisible information to calculate the extractionaccuracy, wherein said simulating comprises utilizing the generatedlayout design of visible information and the generated layout design ofinvisible information; and assessing the calculated extraction accuracy,wherein said assessing comprises ascertaining whether the calculatedextraction accuracy satisfies the predetermined condition and if saidascertaining ascertains that the calculated extraction accuracy does notsatisfy the predetermined condition then performing an iterative loop,wherein each iteration of the loop comprises regenerating the layoutdesign of invisible information followed by performing said simulatingand said assessing, and wherein said loop is terminated uponascertaining that the calculated extraction accuracy satisfies thepredetermined condition.